I keep my GPS turned off most of the time -- more private, and saves battery life too. But there's no way to hide my location from my service provider (I guess I could be in ️ mode most of the time? Maybe an app that puts my phone in airplane mode while the screen is off?)
Android's developer options let you set a GPS location.
If you use developer tools, probably would not work. Because the faked location is clearly marked as debug information. And it will not work for applications that are not specifically reading it.
Edit: Maybe possible for a rooted phone with "unofficial" solution?
Would love to be able to send random coordinates until I make the choice to send an accurate location.